The invention relates to a frame element for placement onto an aquarium container wherein the frame element includes a frame member of angled cross-section which extends around the opening of the aquarium and a web of the frame member is disposed on the top edges of the container walls.
Such a frame element is known from DE-C-34 09 336. This frame element supports a single-or multipart aquarium cover by which the opening of the aquarium-container is covered. The frame element is also used for the mounting of lighting means for illuminating the aquarium from the top that is directing light downward into the aquarium water. Furthermore, the frame element can be used for the mounting and supporting of filters, pumps, and other accessories which complement and improve the usability and appearance of the aquarium.
The known frame element and other, similar frame elements accordingly are provided mainly for supporting covers and lighting means and accessories etc., but have no other functions regarding the aquarium container. The trend in aquariums however is toward larger and larger volume aquarium containers. The aquarium manufacturers try to maintain the basic design features for aquarium containers also for the new large-volume aquarium containers since the aquarium containers have been manufactured for some years now by manufacturing robots. It is tried to maintain the manufacturing procedures as much as possible uniform for the aquarium of all sizes for manufacturing and economical reasons.
Because of industry norms and legal requirements, furthermore, an aquarium filled with water must satisfy certain strength criteria—depending on its size and volume. An essential criteria is the bending elasticity of the front and rear side walls delimiting for example a rectangular aquarium container.
Because of the substantial forces effective on the front and rear walls and also the side walls of large aquarium containers, the maximally admissible bending limit of the walls of such an aquarium container that is the side walls and also the bottom wall which consist of a glass, is reached or even exceeded. The stability of the walls can be increased by thicker sidewalls only to a limited degree, since, on one hand, the aquarium container becomes much heavier and the material and manufacturing costs also increase. On the other hand, glass, which is an optically denser medium than water, causes an optical distortion for the observer of the content of the aquarium container resulting in annoying deformations of the fish and plants in the aquarium and the distortions increase with the thickness of the glass.
There have been attempts to increase the stability also of large-volume aquarium containers by providing reinforcement webs across the opening of the aquarium container or expensive metal frame members have been used which additionally were provided with expensive brace members which were difficult to manufacture. Metallic construction components however are prone to corrosion since they are constantly exposed to water or, respectively, the moist air in the top part of the aquarium container so that only corrosion resistant steel (stainless steel) can be used for such components. This however greatly increased the manufacturing costs for such large volume aquarium containers so that they become unattractive for the consumer.
It is therefore the object of the present invention to provide a frame element for aquarium containers with which also large volume aquarium containers can be stabilized so that their side walls are not bent beyond the normal or legal limits while the frame element remains essentially unchanged so that it can be manufactured by the automatic manufacturing equipment in the same way as smaller containers and, as a result, manufacturing costs remain reasonable. It should also be possible for such a frame element to accommodate cover elements, lighting means and other accessories that is to serve as mounting and support structure. The retaining element should be in principle independent of the selected size of the aquarium.